A blend of availability, tradition, flexibility, compatibility and creativity stimulation helped Legos become more than a toy. They became a platform, a concept, an artistic medium, and mostly, they became a cult. There are a lot of creative applications and creations around, but a few of them are specially worth mentioning.
The minifig society
Supposedly there are billions of minifigs in the world. Pretty impressive. They come in thousands of types and some of the greatest fans were actually able to make a detailed timeline of the minifigs. The Star Wars edition alone has more than 150 different minifigs, and this poster just makes you want to have 'em all.
There are a few cool pages that combine Legos with photography. If you're interested in that sort of stuff, you should check out album covers in Lego, or this amazing classic photography reconstructions.
Perhaps even more popular than pictures, the video edits range from Star Wars videos, arcade games simulations and funny films, such as The Dark Knight trailer. One of the most popular is The Simpsons intro. I've said it before, people have too much time.
Since Mindstorms came around, Legos gained eyes, ears, hands and programming logic. This means that things such as a money safe, Rubic cube solver or even the Touring machine (a primitive computer) are possible to build. The only limit is one's creativity and sadly, budget.
Artistic and giant Lego sets are being built by many people. Diversified lists can be found here, here and here. Other sculptures worth mentioning are the aircraft carrier and the Space Shuttle. Some other freaks made a 5 million brick boulder, which accidentally crashed into a car. The number of bricks is unconfirmed, because in England they made a 30m tall tower using just 500.000 of them. Below you can see Barack Obama's inauguration.
The Millenium Falcon
The Ultimate Collector's Millenium Falcon (that's Harisson Ford's space ship in Star Wars) is the biggest Lego set ever made. You can describe it in one word: Awesome. 5.195 pieces and a price tag of 500€. Ouch. Still, it is probably every Lego fan's dream.
There you have it, Lego fun for the whole family and all the different tastes. I told you Legos were cool.